Return rejected because dependent was claimed by someone else and she is now my Dependent and in my care, what should I do? She's been living with me since August 2017.

I have the form from Hamilton County Superior Court No. 1, that states I have full custody now and my Daughter has been living with me since.  I paid child support until January 8, 2018, which the former Guardian received and kept.  Please help on this.